1. Field of the Invention
The present invention relates to an ice maker of a refrigerator, and more particularly, to an ice maker of a refrigerator that is capable of automatically controlling the entire process from supplying water for making ice to separating the ice and storing it in a storage container, and its control method
2. Description of the Background Art
In general, an ice maker is separately installed in a freezing instrument or a refrigerating instrument to make ice by using a cooling cycle provided in the freezing instrument and the refrigerating instrument.
FIG. 1 is a perspective view of an ice maker in accordance with a conventional art, and FIG. 2 Is a schematic view showing the construction of the ice maker in accordance with the conventional art.
The ice maker of the conventional art includes: an ice making vessel 102 mounted at a certain position for receiving cooling air of a refrigerator and having a plurality of partitions 110; an ejector 104 rotatably mounted at an upper side of the ice making vessel 102, separating ice formed by the ice making vessel and transferring the separated ice in a storage container (not shown); a driving motor 106 installed at one side of the ice making vessel 102 and rotating the ejector 104; a heater 108 installed at a lower side of the ice making vessel 102 and supplying heat to the ice making vessel to facilitate separation of ice formed by the ice making vessel 102; and a full ice detecting unit stopping the driving motor 106 when ice making vessel is full of ice.
The ice making vessel 102 includes a plurality of cavities divided by the partitions 110. A storage container (not shown) is disposed at the lower side of the ice making vessel 102 to store ice formed in the ice making vessel 102. A cup 112 is mounted at one side of the ice making vessel 102 to supply water to the cavities, and a control box 114 is mounted at the other side of the ice making vessel 102, having various parts for driving the ice maker such as the driving motor 106.
The driving motor 106 is fixed inside the control box 114, and a drive gear 116 is connected to the driving motor 106.
As the drive gear 116 is geared with a cam shaft 118 fixed at the ejector 104, a rotational force of the driving motor 106 is transferred to the ejector 104.
A thermostat 120 is mounted at one side of the ice making vessel 102 to sense a temperature inside the ice making vessel and turn on or turn off the heater 108 and the driving motor 106.
The thermostat 120 is formed as a bimetal type to turn on/off a power source applied to the heater 108 and the driving motor 106 according to a temperature of the ice making vessel 102.
An operating switch (not shown) is disposed at the cam shaft 118 to switch on/off a valve (not shown) installed at a supply passage for supplying water to the cup 112. That is, as the operating switch is turned on/off a power supply according to rotation of the cam shaft 118, the power source applied to the valve (not shown) is turned on/off so as to control water supply to the ice making vessel 102.
The full ice detecting unit includes a detecting lever 122 positioned at the storage container and rotatably mounted at the control box 114, and a detecting switch 124 connected to the detecting level 122 and turning off the ice maker when ice is full of the storage container according to rotation of the detecting lever 122.
That is, in the full ice detecting unit, when ice is full of the storage container, the detecting lever 122 is moved upwardly so as to be limited in its rotation movement, and accordingly, the detecting switch is turned off to cut off a power supply applied to the ice maker.
The operation of the ice maker of a refrigerator in accordance with the conventional art will now be described.
When water filled in each cavity of the ice making vessel 102 is frozen by cooling air supplied from a cooling system, the thermostat 120 senses a temperature of the ice making vessel and operates the heater 108.
Then, the heater 108 heats the ice making vessel to facilitate separation of ice formed in the ice making vessel 102.
When the temperature of the ice making vessel increases to a certain degree due to heating by the heater 108, the power supplied to the heater 108 is cut off by the operation of the thermostat 120 and a power supply is applied to the driving motor 106.
Then, the drive gear 116 is rotated according to driving of the driving motor 106, the cam shaft 118 geared with the drive gear 116 is rotated, the ejector 104 is rotated according to rotation of the cam shaft 118, so as to separate ice formed in the ice making vessel 102 and transfer the separated ice to the storage container disposed at a lower side of the ice making vessel 102.
When the cam shaft 118 is rotated, an operating switch (not shown) adjacent to the cam shaft 118 is turned on. As the operating switch is turned, on, the valve is operated to open a supply passage and then water is supplied to the ice making vessel 102 through the cup 112.
The water amount supplied to the ice making vessel 104 is determined by the interval of a cam formed at the cam shaft 118, a time during which the operating switch is maintained ON.
When the storage container is full of ice by the ice making operation, the detecting lever 122 is limited in its rotation due to the ice, and as the detecting switch 124 is turned off according to operation of the detecting lever 122, the operation of the ice maker is stopped.
However, the ice maker of a refrigerator in accordance with the conventional art constructed and operated as described above has many problems.
That is, first, since the supply time is determined by the rotation angle of the cam shaft, that is, the mechanical operation interval of the cam, and the water supply amount is accordingly determined, if an error occurs to the rotation of the cam shaft, water amount supplied to the ice making vessel differs, and thus, the size of ice is different and a defective occurrence rate is high.
Secondly, once the water supply amount is determined, it is not controllable anymore, the size of formed ice is not controllable.
Thirdly, after the ice making vessel is installed, it is not possible to determine a propriety of a water amount supplied to the ice making vessel.
Fourthly, since the thermostat for sensing a temperature of the ice making vessel is formed as a bi-metal type, it is difficult to accurately detect a temperature, and thus, an error occurs due to the thermostat and a defective proportion increases.
Fifthly, since there is no function for testing an operation state of the ice making vessel, it is not possible to recognize malfunction of the ice maker.
Lastly, since the conventional ice maker of a refrigerator does not have a structure for blocking circuit components installed in a case from moisture, a temperature difference takes place in a process that the door of the refrigerator is repeatedly opened and shut, and due to the temperature difference, the inside of the case is frozen or a water drop is generated. This would cause an electric leakage and a fire of the circuit components, resulting in a problem to an operation of the circuit components and that a normal controlling is not possible.
Therefore, a first object of the present invention is to provide an ice maker of a refrigerator that is capable of automatically controlling the entire process of supplying water to an ice making vessel, operating an ejector after completion of ice making and storing the formed ice in a storage container by having a control system for automatically controlling each driving element of an ice maker, and its control method.
A second object of the present invention is to provide an ice maker of a refrigerator that is capable of controlling a size of ice formed by controlling an amount of water supplied to an ice making vessel according to a user""s selection, and its control method.
A third object of the present invention is to provide an ice maker of a refrigerator that is capable of reducing an operation error and improving a performance by adopting a thermistor type temperature sensor for detecting a temperature of an ice making vessel, and its control method.
A fourth object of the present invention is to provide an ice maker of a refrigerator that is capable of preventing a deficiency due to water introduced into circuit components by molding various circuit components controlling an ice maker to block water from being introduced into the circuit components, and its control method.
A fifth object of the present invention is to provide an ice maker of a refrigerator that is capable of preventing a damage to circuit components due to cooling air generated due to an ice making operation by constantly maintaining a temperature inside a control box to which the circuit components are inserted, and its control method.
A sixth object of the present invention is to provide an ice maker of a refrigerator that is capable of preventing occurrence of deficiency in advance by recognizing whether each element of an ice maker is normally operated before an ice making operation or after installation of an ice maker, and its control method.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided an ice maker of a refrigerator including: an ice making vessel having a plurality of cavities; an ejector for separating ice formed in the cavity from the ice making vessel and discharging the ice to a storage container; a driving unit for driving the ejector; a heater disposed at a lower side of the ice making vessel and heating the ice making vessel; a temperature sensor disposed at one side of the ice making vessel and sensing a temperature of the ice making vessel; a full ice detecting unit for generating an electric signal when the storage container is full of ice; and a control unit for receiving the electric signal outputted from the full ice detecting unit and the temperature sensor so as to control an operation of the driving unit and the heater, and turning on/off an input power supply according to the electric signal outputted from the full ice detecting unit.
In the ice maker of a refrigerator of the present invention, the ice making vessel having a plurality of cavities separated by partitions includes a water supply unit installed to supply water into the cavities at one side and a control box having the control unit and the driving unit installed at the other side thereof.
In the ice maker of a refrigerator of the present invention, the water supply unit includes a cup connected to the cavity of the ice making vessel, a water supply tube connected to the cup and supplying water to the cup, and a open-and-shut valve installed at one side of the water supply tube and performs a switching operation on the water supply tube.
In the ice maker of a refrigerator of the present invention, the open-and-shut valve is formed as a solenoid type which opens the water supply tube when a power supply is applied thereto.
In the ice maker of an refrigerator of the present invention, the control box includes a plate having the ejector rotatably disposed and the driving unit and a case for receiving various circuit components of the ice maker, and a display panel is installed at a front side thereof.
In the ice maker of an refrigerator of the present invention, the circuit components inserted into the control box is molded so as to cut off water from being introduced thereto from outside.
In the ice maker of a refrigerator of the present invention, the driving unit includes a driving motor fixed at the plate and generating a rotational force; a driving gear connected to the rotational shaft of the driving motor; and a driven gear connected to the rotational shaft of the ejector and being geared with the driving gear.
In the ice maker of an refrigerator of the present invention, the temperature sensor is formed as a thermistor type so that its electric resistance value is varied according to a temperature change of the ice making vessel and a corresponding electric signal is applied to the control unit.
In the ice maker of a refrigerator of the present invention, the full ice detecting unit includes a sensing bar rotatably connected to the plate and positioned at the storage container so as to be rotated as the storage container is full of ice; and a magnet switch having a first magnet mounted at a tip portion of the sensing bar and a second magnet installed at one side of the driven gear and applying an electric signal to the control unit when the first magnet and the second magnet are positioned on a straight line according to the rotation of the sensing bar.
In the ice maker of a refrigerator of the present invention further includes an ice size controlling unit for controlling a size of ice formed in the cavities of the ice making vessel.
In the ice maker of a refrigerator of the present invention, the ice size controlling unit includes a control lever installed at the display panel and operated to select a size of ice by a user; and a control unit for controlling an opening time of the switch valve of the water supply unit according to an electric signal applied from the control lever.
To achieve the above object, there is also provided an ice maker of a refrigerator including: an ice making vessel having a plurality of cavities; an ejector for separating ice formed in the cavity from the ice making vessel and discharging the ice to a storage container; a driving unit for driving the ejector; a temperature sensor disposed at one side of the ice making vessel and sensing a temperature of the ice making vessel; a control box disposed at one side of the ice making vessel and storing the driving unit and various circuit components; and a temperature maintaining unit installed at the control box and constantly maintaining a temperature inside the control box to prevent a damage to the circuit components due to cooling air generated according to an ice making operation.
In the ice maker of a refrigerator of the present invention, the temperature maintaining unit includes a heater installed inside the control box and heating circuit components to a certain temperature; a temperature sensor installed inside the control box and detecting a temperature of the circuit components; and a control unit operating the heater according to an electric signal applied from the temperature sensor.
To achieve the above object, there is also provided an ice maker of a refrigerator including: an ice maker of a refrigerator including: an ice making vessel having a plurality of cavities; an ejector for separating ice formed in the cavity from the ice making vessel and discharging the ice to a storage container; a driving unit for driving the ejector; a temperature sensor disposed at one side of the ice making vessel and sensing a temperature of the ice making vessel; a display panel installed at a front side of the ice making vessel and displaying an ice making operation; a water supply unit supplying water to the cavities; and a test unit informing a user whether each element of the ice maker is normally operated.
In the ice maker of a refrigerator of the present invention, the test unit includes a test button installed at one side of the display panel and being operated by a user; a control unit performing a testing on each element when the test button is operated; an informing unit for informing the user of a defective element; and a locating sensor installed at one side of the driving unit and detecting a rotational position of the driving unit.
In the ice maker of a refrigerator of the present invention, the informing unit is installed at the display panel and includes a plurality of warning lamps prepared by each element, so that a warning lamp corresponding to a deflective element blinks.
In the ice maker of a refrigerator of the present invention, the locating sensor is installed at one side of the driving unit and formed as a magnet switch type so as to apply an electric signal to the control unit when the rotational position of the driving unit is accurately aligned.
To achieve the above objects, there is further provided a control method of an ice maker of a refrigerator including: a first step in which a power switch is turned on and a switch valve is opened to supply water to an ice making vessel; a second step in which an opening time of the switch valve reaches a pre-set value; a third step in which the switch valve is turned off and an ice making operation is performed, if it is determined that the opening time of the open-and-shut valve has reached a pre-set time; a fourth step in which it is determined that a temperature of the ice making vessel has reached a pre-set value; a fifth step in which a heater is turned on if it is determined that the temperature of the ice making vessel has reached a pre-set value; a sixth step in which a driving motor is driven when a certain time elapses after the heater is operated; and a seventh step in which the power switch is turned off if a storage container is full of ice.
In the control method of an ice maker of a refrigerator of the present invention, the second step includes a step in which a user selects a size of ice, and a step in which an opening time of the open-and-shut valve is controlled as the size of ice is selected.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.